JP2006312184A - Press working device and press working method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press working device capable of reducing warpage at the vertical wall parts, and also, capable of achieving a highly accurate formed component. <P>SOLUTION: The press working device is provided with a punch 2, an outer die 3, an inner die 4, and a blank holder 6 for clamping both end side parts of a metal plate 5 together with the outer die 3. The device is composed so that a metal-pressed component, which has a formed head part, the vertical wall parts respectively continuous to the formed head part, and flange parts respectively continuous to each vertical wall part, is drawn by executing second forming for forming the metal plate into a prescribed shape by pushing the inner die into a space between the punch and the outer die after executing first forming for deep-drawing the metal plate by protruding the punch subsequently to the clamping of both end side parts of the metal plate with the outer die and the holder. The device is also provided with a pressurizing force increasing mechanism 7, which increases the pressurizing force for clamping the flange parts 1c, 1c of the metal plate with the holder and the outer die, at a part being the outside of the metal plate where the blank holder 6 and the outer die 3 are oppositely arranged. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a press working apparatus and a press working method for performing deep drawing, and in particular, to a technique for reducing vertical wall warpage occurring in a metal press part.

  When performing so-called hat drawing forming, in which a metal plate is squeezed with a punch and a die to form a substantially U-shaped cross section and flange portions are formed at both ends thereof, warpage is likely to occur in the vertical wall portion. This warp is called wall warp, but if wall warp occurs, product dimensional accuracy is significantly deteriorated.

  Conventionally, it is known that a defect phenomenon such as wall warp is remarkably reduced by applying a tension to a product standing wall (see, for example, Non-Patent Document 1). That is, this effect can be obtained by increasing the wrinkle pressing load during molding (by pressing the flange portion strongly and applying a load).

However, a high-tensile steel plate (high-tensile material), which is a steel plate having a high tensile strength, is inferior in formability. Therefore, if the wrinkle holding load is set high from the initial stage of forming, cracking occurs and it becomes impossible to form. Therefore, for materials such as high-strength steel sheets that are inferior in formability, the so-called wrinkle-holding load is applied by lowering the wrinkle-holding load at the initial stage of molding and applying tension by increasing the wrinkle-holding load at the latter stage of molding. It is effective to change the above (for example, see Patent Document 1).
Press Forming Difficulty Handbook (1997, P190 and P191), Thin Steel Sheet Forming Technology Study Group (edited), Nikkan Kogyo Shimbun (Publisher) JP 2000-271661 A

  By the way, in the technique described in Patent Document 1, as an effect of dividing and forming the die, in addition to a reduction in the amount of bending and bending back deformation, reduction of a defective phenomenon (wall warpage) due to tension applied to the standing wall portion is given. ing.

  However, in the technique described in Patent Document 1, no specific mechanism related to the control of the tension addition has been proposed, and it is difficult to apply a larger tension.

  In general, as a mechanism to control the tension applied to the standing wall, press equipment that changes the wrinkle holding load during molding has been put into practical use, but the cost is high and a special mold structure that matches the equipment is the same. Since it cannot be produced in a place without a lot of equipment, it is difficult to adopt a wide range.

  Therefore, the present invention has been proposed in view of the above-described actual situation, and even when a high-strength material such as a high-strength steel plate is used without a complicated structure, the warp of the vertical wall portion is reduced. An object of the present invention is to provide a press working apparatus and a press working method capable of obtaining a molded part with high accuracy.

  The press working apparatus of the present invention includes a punch, an outer die, an inner die that is relatively movable inside the outer die, and a holder that clamps both side portions of the metal plate with the outer die, After pressing both ends of the metal plate between the outer die and the holder, the punch is protruded to perform a first forming for deep drawing, and then the inner die is formed between the punch and the outer die. Is a device for drawing a metal press part having a forming head, a vertical wall portion connected to the forming head, and a flange portion connected to the vertical wall portion. is there. Further, in the present apparatus, the pressurization increase that increases the pressurization force that sandwiches the flange portion of the metal plate between the holder and the outer die on the outer side of the metal plate and between the holder and the outer die. A mechanism is provided.

  On the other hand, in the press working method of the present invention, the first forming is performed in which both ends of the metal plate are clamped between the outer die and the holder and then the punch is protruded to deep-draw the metal plate. The second die is formed by pressing the inner die between the die and forming the metal plate into a metal press part having a forming head, a vertical wall portion connected to the forming head, and a flange portion connected to the vertical wall portion. Further, in the present method, after the bottom dead center of the first forming, the pressing force for sandwiching the flange portions corresponding to both end portions of the metal plate is increased, or the pressing force is increased stepwise in the first forming. Let

  According to the press working apparatus of the present invention, the pressurizing force that increases the pressing force that sandwiches the flange portion of the metal plate between the holder and the outer die at the outer portion of the metal plate and between the holder and the outer die. Since the pressure increasing mechanism is provided, the wrinkle holding load can be controlled with general-purpose press equipment, and a molded product with high product dimensional accuracy in which the warp of the vertical wall portion is reduced can be molded anywhere.

  Further, according to the press working method of the present invention, after the bottom dead center of the first forming, the pressing force for pressing the flange portions corresponding to the both end sides of the metal plate is increased, so that a sufficiently strong wrinkle pressing load can be applied. Therefore, the warp of the vertical wall portion can be reduced. Accordingly, it is possible to obtain a metal stamped part with high product dimensional accuracy.

  Further, according to the press working method of the present invention, since the pressing force is increased stepwise in the first molding, a sufficiently strong wrinkle pressing load is applied even to a portion where molding is difficult, and the vertical wall portion Therefore, it is possible to obtain a metal press part with high product dimensional accuracy.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  First, the metal press part shape | molded with the press processing apparatus and press processing method of this invention is demonstrated.

  As shown in FIGS. 1 and 2, a metal press part 1 formed by a press working apparatus and a press working method according to the present invention includes a forming head (hat head) 1 a and vertical wall portions 1 b and 1 b connected thereto. And a flange portion 1c, 1c continuous with the vertical wall portions 1b, 1b.

  For automobile parts, the metal press part 1 having such a cross-sectional hat shape is often used. Further, the metal press part 1 has the lengths of the vertical wall portions 1b and 1b from long to short, or the same part may have a different length depending on the part.

  In order to draw such a metal stamped part 1, the metal plate is formed with a punch and a die in a state where both ends of the metal plate are clamped. As shown in FIG. 3, the wall warp that the vertical wall portions 1b and 1b open to each other occurs. Therefore, by increasing the pressing force that sandwiches the flange portions 1c and 1c, a tensile force is applied to the vertical wall portions 1b and 1b to reduce the residual moment and reduce the wall warp. By doing so, it is possible to obtain a metal press part 1 having high product dimensional accuracy without warping in the vertical wall portions 1b and 1b as shown in FIG.

  The present embodiment is characterized by a mechanism for clamping the flange portions 1c and 1c and a clamping method thereof. Below, the press processing apparatus and press processing method of this Embodiment are demonstrated.

“First Embodiment”
FIG. 3 is a cross-sectional view of the press working apparatus according to the first embodiment, FIG. 4 is an enlarged cross-sectional view of a pressurizing mechanism provided in the press working apparatus according to the first embodiment, and FIG. FIG. 6 is a sectional view of the press working apparatus at the first molding bottom dead center, and FIG. 7 is a sectional view of the press working apparatus at the second molding.

  As shown in FIG. 3, the press working apparatus according to the first embodiment includes a punch 2, an outer die 3, an inner die 4 that is relatively movable inside the outer die 3, and both ends of a metal plate 5. A blank holder 6 that is a holder for clamping the flange portions 1c and 1c, which are side portions, with the outer die 3, and a pressing force that increases the pressing force (wrinkle pressing load) for clamping the flange portions 1c and 1c as necessary. And an increase mechanism 7. The press machine is a general-purpose double action press used in this kind of field.

  The punch 2 is provided so as to move up and down on a lower mold base (not shown). In a state before molding, the blank holder 6 is supported by a plurality of cushion pins 8 provided on the base, and the mounting surface (upper surface) on which the metal plate 5 is placed is flush with the front end surface of the punch 2. Yes. Further, the blank holder 6 is pressed by the outer die 3 during first molding, which will be described later, so that the cushion pin 8 is compressed and lowered to the base side, and the cushion pin 8 is elastically restored after the second molding is completed. It returns to the original position (the same as the front end surface of the punch 2).

  The outer die 3 is fixed to an upper mold plate (not shown). The outer die 3 is lowered during the first molding, and the flange portions 1c and 1c of the metal plate 5 are sandwiched by the blank holder 6 from the thickness direction. Press. The die shoulder portion 3 a of the outer die 3 has a radius larger than the product shape of the metal press part 1. Therefore, the amount of bending and bending back deformation is reduced, and the amount of wall warp is reduced. In drawing, the material is deformed once it flows into the mold and then bent back in the opposite direction (bend-bend deformation), which causes a stress distribution within the material, which is elastic. The wall warp occurs by recovering. This wall warp can be reduced by making the die shoulder radius 3a of the outer die 3 larger than the product shape.

  The inner die 4 is provided inside the outer die 3 and is movable relative to the outer die 3. Similarly to the outer die 3, the die shoulder portion 4 a of the inner die 4 has a larger radius than the product shape of the metal stamped part 1 in order to reduce shoulder warpage.

  As shown in FIG. 4, the pressurizing force increasing mechanism 7 is further contracted by applying a load to the outer die 3 after the bottom dead center of the first molding described later, and pinching the flange portions 1 c and 1 c of the metal plate 5. The pressurizing force is increased by reducing the gap between the plate thickness and the pressure increasing member 9 which is elastically deformable to return to the original state when the load is released, and the pressing force compressing the pressing force increasing member 9 It consists of the member 10. The pressurizing force increasing mechanism 7 is provided at a position that does not interfere with molding, that is, outside the metal plate 5 and at a portion where the blank holder 6 and the outer die 3 are opposed to each other.

  The pressing force increasing member 9 is formed of the same metal material as that of the mold, but a rubber material or the like may be used for a part of the upper surface or the lower surface in order to further promote elastic deformation. The pressurizing force increasing member 9 is fixed on a step surface 6a, which is a position one step lower than the placement surface on which the metal plate 5 is placed, at a portion of the blank holder 6 away from the forming position. This pressurizing force increasing member 9 is kept in contact with the pressing member 10 during the first molding, but for the first time by further applying a load to the outer die 3 past the bottom dead center of the first molding. From this point of time, it is compressed and contracted.

  The pressing member 10 is made of, for example, a rigid plate, and the clearance between the portions that contact the pressing force increasing member 9 and clamp the flange portions 1c and 1c of the metal plate 5 during the first molding is set to a clearance of about the plate thickness. The pressure increasing member 9 is compressed after the first molding bottom dead center to increase the pressing force by making the gap smaller than the plate thickness. The pressing member 10 is fixed to a step surface 3b that is positioned one step lower than the surface that sandwiches the flange portions 1c and 1c.

  By the way, since a molded product such as a body of an automobile has a complicated shape, there are some which have different drawing depths depending on the part. When molding such a part, if the same wrinkle pressing load is applied to all the parts, a load is applied so that the part with a deep drawing depth is not broken, and tension is applied to the vertical wall portions 1b and 1b. become. If such a load is applied, sufficient tension may not be applied to the vertical wall portions 1b and 1b at the portion where the drawing depth is shallow. Therefore, depending on the part where the drawing depth is different (that is, the part where the molding difficulty is different), the height of the pressure increasing member 9 is changed to give the first stage load change.

  In order to make the metal plate 5 into a hat cross-sectional shape as shown in FIG. 1 using the press working apparatus configured as described above, first, as shown in FIG. 3, the punch 2 and the blank holder which are flush with each other. The metal plate 5 is placed on the placement surface which is the upper surface of 6. Next, 1st shaping | molding is performed. That is, as shown in FIG. 5, only the outer die 3 is lowered to the side on which the metal plate 5 is placed, and the flange portions 1c and 1c, which are both ends of the metal plate 5, are connected to the blank holder 6 and the It is sandwiched between the outer die 3. Further, the blank die 6 is pushed downward by lowering the outer die 3 and compressing the cushion pin 8, and the punch 2 is protruded upward. By projecting the punch 2 upward, a molding site which is a central portion of the metal plate 5 in which the flange portions 1c and 1c are clamped by the outer die 3 and the blank holder 6 is molded.

  In the first molding, the entire molding is performed under the condition of a low wrinkle pressing load that can be sufficiently molded by the outer die 3. That is, drawing is performed by the punch 2 while sandwiching the flange portions 1c and 1c so as to have the same low wrinkle pressing load in all the longitudinal direction portions of the metal press part 1 having a hat cross-sectional shape.

  During the first molding, as shown in FIG. 4 (B), the pressing member 10 abuts against the pressing force increasing member 9 provided at a position corresponding to the pressing member 10 and clamps the flange portions 1c and 1c. The gap (clearance) between the blank holder 6 and the outer die 3 is held so as to be a gap of about the plate thickness. Further, during the first molding, since the wrinkle holding load is weaker than the molding load, molding is performed while the gap is kept substantially equal to the plate thickness due to the height of the pressure increasing member 9. At this time, although the molding load is high, since the cushion pin 8 is pushed and moves, the mold does not exceed the wrinkle pressing load.

  When the molding by the outer die 3 reaches the bottom dead center, as shown in FIG. 6, the cushion pin 8 is crushed, and the blank holder 6 is brought into contact with the base and cannot move. Further load is applied to the outer die 3 from the bottom dead center state. Then, as shown in FIG. 4C, the outer die 3 bends, the pressure increasing member 9 contracts, and the pressure (wrinkle pressing load) for clamping the flange portions 1c and 1c increases.

  Then, after the wrinkle pressing load increases, as shown in FIG. 7, the inner die 4 is pushed between the punch 2 and the outer die 3 to perform the second molding. In the second molding by the inner die 4, since the wrinkle pressing load for sandwiching the flange portions 1 c and 1 c is increased, the inflow of material is reduced (or fastened), so the vertical wall portions 1 b and 1 b Strong tension works.

  As described above, according to the press working method of the present embodiment, after the bottom dead center of the first molding, the pressing force (wrinkle pressing load) sandwiching the flange portions 1c, 1c is increased, and the second molding by the inner die 4 is performed. Since a strong pulling force can be applied to the vertical wall portions 1b and 1b, the wall warp of the vertical wall portions 1b and 1b can be greatly reduced. Therefore, the metal press part 1 obtained by the method of the present invention is a molded product having a high dimensional accuracy with very little wall warpage.

  Further, according to the press working apparatus of the present embodiment, wrinkle holding load control (load increase control) can be performed with a general-purpose press without using a press equipped with special equipment. Molding is possible anywhere, not limited to a well-equipped place. Further, according to the press working apparatus of the present embodiment, wrinkle holding load control can be performed with a simple structure in which the pressing force increasing mechanism 7 composed of the pressing force increasing member 9 and the pressing member 10 is provided at a location that does not interfere with molding. Therefore, the metal press part 1 with high dimensional accuracy can be manufactured at low cost.

  FIG. 8 is a diagram for determining an appropriate processing condition in the case of molding a material having excellent formability (metal plate 5) and a material having inferior formability. For example, when forming a material having poor formability such as a high-tensile steel plate (high-tensile material), as shown in FIG. 8A, when the second forming is started from the bottom dead center, the vertical wall portions 1b, 1b May crack. When the wrinkle holding load is high and the inflow of the material is completely stopped, the vertical wall portions 1b and 1b are positioned from the broken line (line A) to the solid line (the standing wall shape after molding) as shown in FIG. This elongation amount exceeds the limit of elongation due to the lack of moldability of the material itself and the amount of deformation so far, and cracks occur.

  On the other hand, the material excellent in moldability, because even if the inner die 4 is lowered from the bottom dead center of the first molding and the second molding is started, sufficient tension is applied to the vertical wall portions 1b and 1b. The vertical wall portions 1b and 1b are not cracked.

  When molding a material inferior in moldability, as shown in FIG. 8C, at the bottom dead center of the first molding, the vertical wall portions 1b and 1b are in a state indicated by a one-dot chain line (B line). Then, the punch 2 and the inner die 4 are controlled, and then the inner die 4 is lowered to the bottom dead center. That is, during the first molding or simultaneously with the start of the first molding, the inner die 4 is lowered and pressed between the punch 2 and the outer die 3 to perform the molding. If molding is performed at such timing, the required deformation amount is reduced, and molding can be performed without causing cracks.

  In the embodiment described above, a member that elastically deforms and expands and contracts is used as the pressure increasing member 9, but instead of this elastically deforming member, three parts having a wedge shape are used as shown in FIG. 9. Among the pressurizing force increasing members 9A, 9B, 9C, the central pressurizing force increasing member 9B is connected to the rod 12 of the air cylinder 11, and the height of the entire pressurizing pressure increasing member 9 is variable by allowing the rod 12 to be retractable. Even if it is made to do, the same effect is acquired.

“Second Embodiment”
FIG. 10 is an enlarged cross-sectional view of a pressurizing force increasing mechanism provided in the press working apparatus according to the second embodiment, FIG. 11 shows the pressurizing force increasing mechanism in a state before molding, (A) is a plan view, and (B) ) Is a longitudinal sectional view, FIG. 12 is a longitudinal sectional view showing a pressing force increasing mechanism in the first stage of the first molding, and FIG. 13 is a longitudinal sectional view showing the pressing force increasing mechanism in the first stage of the first molding.

  In the press working apparatus of the second embodiment, the punch 2, the inner die 4, the outer die 3, the blank holder 6 and the like are the first except that the configuration of the pressure increase mechanism is different from that of the first embodiment. Since the configuration is the same as that of the embodiment, the description of overlapping portions is omitted. Here, the pressure increase mechanism 20 will be described.

  As shown in FIGS. 10 and 11, the pressurizing force increasing mechanism 20 is configured to maintain the gap at the portion where the flange portions 1 c and 1 c are clamped in the first stage of the first molding with a gap substantially the same as the thickness of the metal plate 5. The first block 21 that is a first pressure increasing member that applies pressure (wrinkle pressing load) and a second pressure increasing member that further increases the pressure by reducing the gap in the latter stage of the first molding. 2 blocks 22, a contact member 23 in contact with the first block 21 and the second block 22, and a bend that lowers the height of the first block 21 by bending the first block 21 at the later stage of the first molding. And means 24.

  The first block 21 has a large-diameter cylindrical portion 21A that comes into contact with the abutting member 23 fixed to the step surface 3b of the outer die 3, and a cylindrical shape divided into two provided at the lower end of the large-diameter cylindrical portion 21A. The first support column 21B and the second support column 21C. The large-diameter cylindrical portion 21A, the first support column 21B, and the second support column 21C are all movably connected to each other, and the connection portion is a return means that returns to the original state after the molding is completed. A torsion coil spring 25 is provided. The torsion coil spring 25 supports the large-diameter cylindrical portion 21A, the first support column 21B, and the second support column 21C so as to form a straight column in the initial state.

  The large-diameter cylindrical portion 21A and the first support column 21B are formed with flank surfaces 26 so that they do not interfere with each other (do not collide with each other) when bent between the support columns by a bending means 24 described later.

  The second block 22 is provided outside the first block 21 and is formed as a cylindrical column having a slightly lower height than the first block 21. The second block 22 is formed with a circular through hole 27 that penetrates from the outside to the inside. The through hole 27 is provided at a position corresponding to the connecting portion between the first support column 21B and the second support column 21C of the first block 21.

  The bending means 24 includes a cylindrical pin 28 inserted into the through hole 27 and a slide holding member 29 that slidably holds the pin 28. The slide holding member 29 is provided at a position close to the second block 22 and is fixed to the blank holder 6 described above. The pin 28 is held so as to be slidable in the horizontal direction with respect to the slide holding member 29, and is slid at the latter stage of the first molding, and the connecting portion between the first support column 21B and the second support column 21C is pushed in at the tip thereof. Then, the first block 21 is bent.

  An air source in the factory is used as a power source for sliding the pin 28 without using a large driving mechanism such as a motor. Therefore, the wrinkle holding load can be adjusted with a small small force. In addition, an air cylinder that operates using an air source in the factory can be used as the bending means 24.

  In order to make the metal plate 5 into a hat cross-sectional shape as shown in FIG. 1 using the press working apparatus having the pressurizing force increasing mechanism 20 configured as described above, as in the first embodiment, a punch is used. 2 and the metal plate 5 are placed on the mounting surface which is the upper surface of the blank holder 6. At this time, the height of the first block 21 is maintained higher than that of the second block 22.

  Then, the outer die 3 is lowered, the flange portions 1c and 1c of the metal plate 5 are clamped by the outer die 3 and the blank holder 6, and the punch 2 is protruded upward to perform the first molding. In the first stage of the first molding, as shown in FIGS. 10B and 12, the contact member 23 comes into contact with the tip of the first block 21, and the gap is substantially the same as the thickness of the metal plate 5. To be kept. Therefore, in the first stage of the first molding, the flange portions 1c and 1c are clamped by the initial wrinkle pressing load and molding is performed.

  Next, when the second stage of the first molding is reached, the bending means 24 is operated to project the pin 28 and push the connecting portion between the first support 21B and the second support 21C of the first block 21. The first block 21 is bent halfway. Then, as shown in FIG. 10C and FIG. 13, the first block 21 is bent near the center from the side by the pin 28, so that the column is bent and its height is higher than the height of the second block 22. Lower.

  As a result, the contact member 23 comes into contact with the tip of the second block 22 from the first block 21. As a result, the gap (clearance) between the blank holder 6 and the outer die 3 is reduced by the height difference (change amount) between the first block 21 and the second block 22 set in the initial stage, so that wrinkles are reduced. The holding load increases. Therefore, from this point to the bottom dead center, the wrinkle pressing load is increased, so that the inflow of the material is reduced (or is stopped), so that tension can be applied to the vertical wall portions 1b and 1b.

  Then, when the outer die 3 is molded until the bottom dead center is reached, the inner die 4 is pushed between the punch 2 and the outer die 3 to perform the second molding. In the second molding by the inner die 4, the wrinkle pressing load that sandwiches the flange portions 1c and 1c is increased, so that the inflow of the material is reduced, so that strong tension acts on the vertical wall portions 1b and 1b. Thereby, the wall warp of the vertical wall portions 1b and 1b can be greatly reduced, and a molded product having high dimensional accuracy can be obtained.

  Thus, according to the press working method of the present embodiment, the pressurizing force is increased stepwise in the first molding, so that a sufficiently strong wrinkle pressing load is applied even to a portion where molding is difficult. The warp of the vertical wall portions 1b and 1b can be reduced, and the metal press part 1 with high product dimensional accuracy can be obtained. In particular, in the present embodiment, the wrinkle pressing load can be applied to the vertical wall portions 1b and 1b as two levels of strength.

  Further, according to the press working apparatus of the present embodiment, the wrinkle pressing load can be varied by bending the first block 21 instantaneously only by the operation of pushing the pin 28. Moreover, it becomes possible to easily provide desired vertical wall portions 1b and 1b according to the degree of difficulty in forming the metal plate 5.

  Note that the switching time from the first stage to the second stage of the first molding is determined according to the depth of the vertical wall portions 1b and 1b of the metal press part 1.

"Other embodiments"
Although specific embodiments to which the present invention is applied have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

  For example, an embodiment in which the first embodiment and the second embodiment are combined may be employed. For example, when forming the metal plate 5 that is extremely difficult to form, in the first forming, the wrinkle holding load is varied and increased in the first and second stages, and then the wrinkle holding load is further increased after the bottom dead center of the first forming. May be increased.

  In addition, the first embodiment and the second embodiment may be combined for those having different drawing depths depending on the part.

The metal press component shape | molded with the press work apparatus and press work method of this Embodiment is shown, (A) is a perspective view, (B) is a top view. FIG. 2A is a perspective view of a metal press part in a state where wall warpage has occurred, and FIG. 2B is a perspective view of the metal press part in which wall warp has been reduced. It is sectional drawing of the press work apparatus of 1st Embodiment. It is an expanded sectional view of the pressurization force increase mechanism provided in the press work apparatus of a 1st embodiment. It is sectional drawing of the press work apparatus at the time of 1st shaping | molding. It is sectional drawing of the press work apparatus at the time of 1st shaping | molding bottom dead center. It is sectional drawing of the press work apparatus at the time of 2nd shaping | molding. FIG. 8 is a diagram for determining appropriate processing conditions when molding a material (metal plate) having excellent formability and a material having inferior formability. It is sectional drawing which shows the other example of a pressurizing force increase mechanism. It is an expanded sectional view of the pressurizing force increasing mechanism provided in the press working apparatus of the second embodiment. The pressure increase mechanism in the state before shaping | molding is shown, (A) is a top view, (B) is a longitudinal cross-sectional view. It is a longitudinal cross-sectional view which shows the pressurization force increase mechanism in the 1st shaping | molding first stage. It is a longitudinal cross-sectional view which shows the pressurization force increase mechanism in the 1st shaping | molding late stage.

Explanation of symbols

1 ... Metal stamping part 1a ... Molding head (hat head)
1b ... Vertical wall 1c Flange 2 ... Punch 3 ... Outer die 4 ... Inner die 5 ... Metal plate 6 ... Blank holder (holder)
7, 20 ... Pressure increasing mechanism 9 ... Pressure increasing member 10 ... Pressing member 21 ... First block (first pressure increasing member)
22 ... 2nd block (2nd pressurizing force increasing member)
23 ... Contact member 24 ... Bending means 28 ... Pin

Claims (10)

A punch, an outer die, an inner die that is relatively movable inside the outer die, and a holder that clamps both end sides of the metal plate with the outer die, and the outer die and the holder After pressing both ends of the metal plate, the punch is protruded to perform the first forming of the metal plate, and then the inner die is pushed between the punch and the outer die so that the metal plate is fixed. In a press working apparatus for performing a second forming to form a shape and drawing a metal press part having a forming head, a vertical wall portion connected to the forming head, and a flange portion connected to the vertical wall portion,
A pressurization increasing mechanism for increasing the pressurizing force that sandwiches the flange portion of the metal plate with the holder and the outer die is provided on the outer side of the metal plate and opposed to the holder and the outer die. A press working device. The press working apparatus according to claim 1,
The pressing force increasing mechanism further applies a load to the outer die after the bottom dead center of the first molding and shrinks, and applies a gap at a portion that clamps the flange portion of the metal plate as being smaller than the plate thickness. A press working apparatus comprising: a pressure increasing member capable of elastic deformation that increases pressure and returns to its original state when the load is released; and a pressing member that compresses the pressure increasing member. . The press working apparatus according to claim 1,
In the first stage of the first molding, the pressurizing force increasing mechanism is configured to apply a pressurizing force while maintaining a gap at a portion where the flange portion of the metal plate is clamped at a gap substantially the same as the plate thickness of the metal plate. An increasing member, a second pressing force increasing member that further increases the pressing force by reducing the gap, and a contact member that contacts the first and second pressing force increasing members in the latter stage of the first molding A press working apparatus characterized by comprising: The press working apparatus according to claim 3,
The first pressurizing force increasing member is formed as a support column that can be bent in the middle of the height direction, and the second pressurizing force increasing member is a support column that is slightly lower in height than the first pressurizing force increasing member. Formed,
In the first stage of the first molding, the first pressing force increasing member is higher in height than the second pressing force increasing member and comes into contact with the abutting member so that the gap is substantially the same as the thickness of the metal plate. To keep
In the latter stage of the first molding, the first pressurizing force increasing member is bent halfway and its height is lower than that of the second pressurizing force increasing member, so that the contact member is located at the tip of the second pressurizing force increasing member. A press working apparatus, wherein the gap is reduced by contact. It is a press processing apparatus of Claim 4, Comprising:
A press working apparatus comprising bending means for bending the first pressurizing force increasing member to lower its height when the latter stage of the first molding is reached. The press working apparatus according to claim 4 or 5,
The press working apparatus, wherein the first pressurizing force increasing member is provided with return means for returning to the original state after completion of molding. After pressing both ends of the metal plate between the outer die and the holder, the punch is protruded to perform the first forming for deep drawing of the metal plate, and then the inner die is pushed between the punch and the outer die. In the press working method for performing the second forming of forming the metal plate into a metal press part having a forming head, a vertical wall portion connected to the forming head, and a flange portion connected to the vertical wall portion,
A press working method, wherein after the bottom dead center of the first molding, a pressing force for sandwiching flange portions corresponding to both side portions of the metal plate is increased. The press working method according to claim 7,
When the metal plate is a material having excellent formability, the inner die is pushed between the punch and the outer die after the first molding reaches bottom dead center. The press working method according to claim 7,
When the metal plate is inferior in formability, the inner die is pushed between the punch and the outer die during the first molding or simultaneously with the start of the first molding. After pressing both ends of the metal plate between the outer die and the holder, the punch is protruded to perform the first forming for deep drawing of the metal plate, and then the inner die is pushed between the punch and the outer die. In the press working method for performing the second forming of forming the metal plate into a metal press part having a forming head, a vertical wall portion connected to the forming head, and a flange portion connected to the vertical wall portion,
In the first forming, the pressurizing method is characterized in that the pressurizing force for sandwiching the flange portions corresponding to both end portions of the metal plate is increased stepwise.

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